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1.
Brain Res ; 1817: 148469, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37355150

RESUMO

OBJECTIVE: To explore the abnormalities of brain function in blepharospasm (BSP) and to illustrate its neural mechanisms by assuming supplementary motor area (SMA) as the entry point. METHODS: Twenty-five patients with BSP and 23 controls underwent resting-state functional MRI, seed-based functional connectivity (FC), correlation analysis, receiver operating characteristic curve (ROC) analysis, and support vector machine (SVM) were applied to process the data. RESULTS: Patients showed that the left medial prefrontal cortex (MPFC), left lingual gyrus, right cerebellar crus I, and right lingual gyrus/cerebellar crus I had enhanced FC with the left SMA, whereas the right inferior temporal gyrus (ITG) had enhanced FC with the right SMA relative to controls. The FC between the left MPFC and left SMA was positively correlated with symptomatic severity. The ROC analysis verified that the abnormal FCs demonstrated in this study can separate patients and controls at high sensitivity and specificity. SVM analysis exhibited that combined FCs of the left SMA were optimal for distinguishing patients and control group at the accuracy of 89.58%, with sensitivity of 92.00% and specificity of 86.96%. CONCLUSIONS: Several brain networks partake in the neurobiology of BSP. SMA plays a vital role in several brain networks and might be the key pathogenic factor in BSP. SIGNIFICANCE: Providing novel evidence for the engagement of the MPFC in the motor symptoms of BSP, enhancing credibility of the thesis that SMA regulates the neurobiology of BSP, and providing ideas of screening susceptible population of BSP using neuroimaging.


Assuntos
Blefarospasmo , Conectoma , Córtex Motor , Máquina de Vetores de Suporte , Humanos , Blefarospasmo/diagnóstico por imagem , Blefarospasmo/fisiopatologia , Córtex Motor/diagnóstico por imagem , Córtex Motor/fisiopatologia , Descanso , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiopatologia , Masculino , Adulto , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética
2.
Glia ; 71(8): 1906-1920, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37017183

RESUMO

Microglia participates in the modulation of pain signaling. The activation of microglia is suggested to play an important role in affective disorders that are related to a dysfunction of the mesocorticolimbic system (MCLS) and are commonly associated with chronic pain. Moreover, there is evidence that mu-opioid receptors (MORs), expressed in the MCLS, are involved in neuroinflammatory events, although the way by which they do it remains to be elucidated. In this study, we propose that MOR pharmacological activation within the MCLS activates and triggers the local release of proinflammatory cytokines and this pattern of activation is impacted by the presence of systemic inflammatory pain. To test this hypothesis, we used in vivo microdialysis coupled with flow cytometry to measure cytokines release in the nucleus accumbens and immunofluorescence of IBA1 in areas of the MCLS on a rat model of inflammatory pain. Interestingly, the treatment with DAMGO, a MOR agonist locally in the nucleus accumbens, triggered the release of the IL1α, IL1ß, and IL6 proinflammatory cytokines. Furthermore, MOR pharmacological activation in the ventral tegmental area (VTA) modified the levels of IBA1-positive cells in the VTA, prefrontal cortex, the nucleus accumbens and the amygdala in a dose-dependent way, without impacting mechanical nociception. Additionally, MOR blockade in the VTA prevents DAMGO-induced effects. Finally, we observed that systemic inflammatory pain altered the IBA1 immunostaining derived from MOR activation in the MSCLS. Altogether, our results indicate that the microglia-MOR relationship could be pivotal to unravel some inflammatory pain-induced comorbidities related to MCLS dysfunction.


Assuntos
Dor Crônica , Microglia , Doenças Neuroinflamatórias , Córtex Pré-Frontal , Receptores Opioides mu , Área Tegmentar Ventral , Receptores Opioides mu/agonistas , Receptores Opioides mu/metabolismo , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/fisiopatologia , Microglia/metabolismo , Área Tegmentar Ventral/metabolismo , Área Tegmentar Ventral/fisiopatologia , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/fisiopatologia , Animais , Ratos , Modelos Animais de Doenças , Dor Crônica/metabolismo , Dor Crônica/fisiopatologia , Núcleo Accumbens/metabolismo , Núcleo Accumbens/fisiopatologia , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas dos Microfilamentos/metabolismo , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Masculino , Feminino , Ratos Sprague-Dawley
3.
Physiol Behav ; 263: 114107, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36740134

RESUMO

Early life stress (ELS) can set the stage for susceptibility to cognitive and emotional dysfunction in adulthood by disrupting typical neural development. The prefrontal cortex (PFC) continues to mature during early life, making this region particularly vulnerable to disruption for animals who experience ELS. Despite this, the effects of ELS experience on in vivo PFC function in awake and behaving adult animals are currently poorly understood. To assess this, we employed an instrumental conflict task to assess how hungry adult rats, either ELS (wet bedding) or unstressed Controls, were able to flexibly alter their motivation for food reward seeking (lever presses) in situations that were either threatening or safe. During this task, in vivo electrophysiological recordings (both single unit and local field potentials [LFPs]) were made in the rats' ventral-medial PFC (vmPFC). We found that ELS rats were less motivated to lever press for rewards than Controls in the threat situations during repeated extinction sessions. In recordings taken during this suppression task, Control vmPFC neurons displayed reliable differences between motivated actions, such as between rewarded and unrewarded presses, but ELS neurons failed to differentiate these action-outcome differences. We also found differences in task-related LFP activity between groups; in particular, prior ELS experience appears to induce abnormal changes in low-frequency oscillations during shock-associated threat stimuli prior to presses, as well as diminished higher-frequency oscillations following rewarded presses. Collectively, we demonstrate that ELS experience produces persistent impairment in motivational regulation that is associated with significant changes in in vivo PFC signals. Specifically, ELS-experienced adults fail to appropriately update motivated action strategies under threat conditions, and likewise fail to appropriately monitor and update action/outcome relationships in motivated behavior. These ELS-related changes may therefore lay the foundation for heightened susceptibility to mental-health disorders in adults such as substance abuse and post-traumatic stress disorder.


Assuntos
Neurônios , Córtex Pré-Frontal , Estresse Psicológico , Animais , Ratos , Neurônios/patologia , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/fisiopatologia , Recompensa
4.
Behav Brain Res ; 437: 114113, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36108777

RESUMO

Prepulse inhibition (PPI) allows assessing schizophrenia-like sensorimotor gating deficits in rodents. Previous studies indicate that PPI is modulated by the medial prefrontal cortex (mPFC), which is in agreement with our findings showing that PPI differences in the Roman rats are associated with divergences in mPFC activity. Here, we explore whether differences in PPI and mPFC activity in male Roman rats can be explained by (i) differences in the activation (c-Fos) of inhibitory neurons (parvalbumin (PV) interneurons); and/or (ii) reduced excitatory drive (PSD-95) to PV interneurons. Our data show that low PPI in the Roman high-avoidance (RHA) rats is associated with reduced activation of PV interneurons. Moreover, the RHA rats exhibit decreased density of both PV interneurons and PSD-95 puncta on active PV interneurons. These findings point to reduced cortical inhibition as a candidate to explain the schizophrenia-like features observed in RHA rats and support the role of impaired cortical inhibition in schizophrenia.


Assuntos
Interneurônios , Parvalbuminas , Córtex Pré-Frontal , Esquizofrenia , Filtro Sensorial , Animais , Masculino , Ratos , Proteína 4 Homóloga a Disks-Large/metabolismo , Interneurônios/fisiologia , Parvalbuminas/metabolismo , Córtex Pré-Frontal/fisiopatologia , Ratos Endogâmicos , Esquizofrenia/fisiopatologia , Filtro Sensorial/fisiologia
5.
Psychol Med ; 53(3): 823-832, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34154683

RESUMO

BACKGROUND: Major depressive disorder (MDD) and chronic pain are highly comorbid, and pain symptoms are associated with a poorer response to antidepressant medication treatment. It is unclear whether comorbid pain also is associated with a poorer response to treatment with repetitive transcranial magnetic stimulation (rTMS). METHODS: 162 MDD subjects received 30 sessions of 10 Hz rTMS treatment administered to the left dorsolateral prefrontal cortex (DLPFC) with depression and pain symptoms measured before and after treatment. For a subset of 96 patients, a resting-state electroencephalogram (EEG) was recorded at baseline. Clinical outcome was compared between subjects with and without comorbid pain, and the relationships among outcome, pain severity, individual peak alpha frequency (PAF), and PAF phase-coherence in the EEG were examined. RESULTS: 64.8% of all subjects reported pain, and both depressive and pain symptoms were significantly reduced after rTMS treatment, irrespective of age or gender. Patients with severe pain were 27% less likely to respond to MDD treatment than pain-free individuals. PAF was positively associated with pain severity. PAF phase-coherence in the somatosensory and default mode networks was significantly lower for MDD subjects with pain who failed to respond to MDD treatment. CONCLUSIONS: Pain symptoms improved after rTMS to left DLPFC in MDD irrespective of age or gender, although the presence of chronic pain symptoms reduced the likelihood of treatment response. Individual PAF and baseline phase-coherence in the sensorimotor and midline regions may represent predictors of rTMS treatment outcome in comorbid pain and MDD.


Assuntos
Dor Crônica , Transtorno Depressivo Maior , Estimulação Magnética Transcraniana , Humanos , Biomarcadores , Dor Crônica/epidemiologia , Dor Crônica/terapia , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/terapia , Córtex Pré-Frontal/fisiopatologia , Resultado do Tratamento , Comorbidade , Eletroencefalografia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso
6.
Rev. psiquiatr. Urug ; 86(2): 55-61, dic. 2022. ilus
Artigo em Espanhol | LILACS, UY-BNMED, BNUY | ID: biblio-1412357

RESUMO

Se realiza una revisión de estudios de resonancia magnética integral y funcional, así como estudios bioquímicos en pacientes con y sin ideas suicidas. Estos estudios en pacientes con alto riesgo de suicidio presentan una disminución de volúmenes corticales en la corteza prefrontal dorso y ventrolateral. Lo importante de estos estudios es que resultan de la comparación con pacientes deprimidos con bajo riesgo de suicidio. Los estudios de resonancia magnética funcional mostraron una hipofuncionalidad del lóbulo prefrontal en los pacientes depresivos con ideas suicidas severas, que se observa como una disminución del flujo sanguíneo cerebral en las áreas lateral y ventral. Se observa una disminución del metabolismo de serotonina, en clara relación con la severidad de las ideas de muerte, también con un foco en la región lateroventral prefrontal. Dado que las funciones de la corteza prefrontal afirman al individuo en su perspectiva vital, disfunciones como las descritas debilitan la coordinación y organización del apego a la vida, quedando, por el contrario, la posibilidad de la búsqueda de la muerte. Se concluye que los pacientes depresivos con ideas suicidas tienen una alta vulnerabilidad para el intento de suicidio por la afectación de las zonas prefrontales.


A review of functional integral magnetic resonance and biochemical data from patients with and without suicidal ideation is presented. Patients with high suicidal risk show a decrease in cortical volume in ventrolateral and dorsal prefrontal cortex. These studies are compared to those of depressed patients with low suicidal risk. Functional magnetic resonance in depressed patients with severe suicidal ideation show an hypo functional prefrontal lobe, seen as a decrease in blood flow in lateral and ventral areas. There is a decrease in serotonin metabolism, clearly related to the severity of suicidal ideation, also in ventrolateral prefrontal cortex. As prefrontal cortex functions enhance vital perspectives, such dysfunctions weaken coordination and organization of attachment to life, making search for death a possibility. Authors conclude that depressed patients with suicidal ideation have a high vulnerability for suicidal intent due to changes in prefrontal areas.


Assuntos
Humanos , Tentativa de Suicídio , Córtex Pré-Frontal/fisiopatologia , Neurotransmissores/metabolismo , Depressão/fisiopatologia , Ideação Suicida , Imageamento por Ressonância Magnética , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/diagnóstico por imagem , Depressão/metabolismo
9.
Eur J Pain ; 26(7): 1546-1568, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35603472

RESUMO

BACKGROUND: Prelimbic medial prefrontal cortex (PL-mPFC) and nucleus accumbens core region (NAcc) play an important role in supporting several executive cognitive mechanisms, such as spatial working memory (WM). Recently, this circuit has been also associated with both sensory and affective components of pain. However, it is still unclear whether this circuit is endogenously engaged in neuropathic pain-related cognitive dysfunctions. METHODS: To answer this question, we induced the expression of halorhodopsin in local PL-mPFC neurons projecting to NAcc, and then selectively inhibited the terminals of these neurons in the NAcc while recording neural activity during the performance of a delayed non-match to sample (DNMS) spatial WM task. Within-subject behavioural performance and PL-mPFC to NAcc circuit neural activity was assessed after the onset of a persistent rodent neuropathic pain model-spared nerve injury (SNI). RESULTS: Our results revealed that the induction of the neuropathy reduced WM performance, and altered the interplay between PL-mPFC and NAcc neurons namely in increasing the functional connectivity from NAcc to PL-mPFC, particularly in the theta-band spontaneous oscillations; in addition, these behavioural and functional perturbations were partially reversed by selective optogenetic inhibition of PL-mPFC neuron terminals into the NAcc during the DNMS task delay-period, without significant antinociceptive effects. CONCLUSIONS: Altogether, these results strongly suggest that the PL-mPFC excitatory output into the NAcc plays an important role in the deregulation of WM under pain conditions. SIGNIFICANCE: Selective optogenetic inhibition of prefrontal-striatal microcircuit reverses pain-related working memory deficits but has no significant impact on pain responses. Neuropathic pain underlies an increase of functional connectivity between the nucleus accumbens core area and the prelimbic medial prefrontal cortex mediated by theta-band activity.


Assuntos
Memória de Curto Prazo , Neuralgia , Córtex Pré-Frontal , Animais , Transtornos da Memória/complicações , Memória de Curto Prazo/fisiologia , Córtex Pré-Frontal/fisiopatologia , Ratos , Ratos Sprague-Dawley , Ritmo Teta
10.
Molecules ; 27(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35208969

RESUMO

Imperatorin, a naturally derived furanocoumarin, exerts promising neuropharmacological properties. Therefore, it might be applicable in the treatment of brain diseases such as depression. In the present project, we aimed to investigate the sex-dependent effects of imperatorin (1, 5, and 10 mg/kg) on behavior and neurochemistry associated with antidepressant effects. The depressive-like behaviors of male and female Swiss mice were investigated in a forced swim test (FST). Subsequently, High-Performance Liquid Chromatography (HPLC) was used to evaluate the level of serotonin, its metabolite, 5-HIAA, and noradrenaline, in mouse brains. The study revealed that only males responded to imperatorin (1 and 5 mg/kg) treatment and caused an antidepressant effect, such as with respect to depressive-like behaviors, lowering immobility time and increasing immobility latency. The HPLC analysis demonstrated that serotonin levels in the prefrontal cortex of females decreased with the middle dose of imperatorin (5 mg/kg), while in the male prefrontal cortex, the lower dose (1 mg/kg) boosted serotonin levels. There were no evident changes observed with respect to noradrenaline and serotonin metabolite levels in the male hippocampus. To conclude, we propose that imperatorin has antidepressant potential, seemingly only in males, influencing brain serotonin level, but the direct mechanism of action requires further investigation.


Assuntos
Comportamento Animal/efeitos dos fármacos , Depressão , Furocumarinas/farmacologia , Córtex Pré-Frontal , Caracteres Sexuais , Animais , Depressão/tratamento farmacológico , Depressão/metabolismo , Depressão/fisiopatologia , Feminino , Furocumarinas/farmacocinética , Masculino , Camundongos , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/fisiopatologia
11.
Behav Brain Res ; 422: 113763, 2022 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-35063499

RESUMO

Deficits in response inhibition are a central feature of the highly prevalent dysexecutive syndrome found in Parkinson's disease (PD). Such deficits are related to a range of common clinically relevant symptoms including cognitive impairment as well as impulsive and compulsive behaviors. In this study, we explored the cortical dynamics underlying response inhibition during the mental preparation for the antisaccade task by recording magnetoencephalography (MEG) and eye-movements in 21 non-demented patients with early to mid-stage Parkinson's disease and 21 age-matched healthy control participants (HC). During the pre-stimulus preparatory period for antisaccades we observed: Taken together, the results indicate that alterations in pre-stimulus prefrontal alpha and beta activity hinder proactive response inhibition and in turn result in higher error rates and prolonged response latencies in PD.


Assuntos
Ondas Encefálicas/fisiologia , Disfunção Cognitiva/fisiopatologia , Sincronização Cortical/fisiologia , Função Executiva/fisiologia , Inibição Psicológica , Doença de Parkinson/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Movimentos Sacádicos/fisiologia , Idoso , Disfunção Cognitiva/etiologia , Feminino , Humanos , Magnetoencefalografia , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações
12.
Brain Res Bull ; 181: 36-45, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35066097

RESUMO

Ischemia in the medial prefrontal cortex (mPFC) causes cognitive impairment in stroke cases. This study aimed to examine the effects of varenicline as α7 and α4ß2 nicotine acetylcholine receptors (nAChRs) agonist, on cognitive impairment, inflammation, apoptosis, and synaptic dysfunction in mPFC ischemia. Mice were divided to three groups of control, sham, or photothrombotic mPFC ischemia model. The control and sham groups received 2 ml/kg of normal saline for a 14-day period. As well, the animals in the ischemia groups received normal saline (2 ml/kg) or varenicline at 0.1, 1, and 3 mg/kg doses for a 14-day period. Anxiety-like behaviors were then assessed by open field (OFT) and elevated plus-maze (EPM) tests. Memory was also evaluated using Morris water maze (MWM) and novel object recognition (NOR) tests. The levels of inflammatory (IL-1ß, TNF-α), apoptotic (Bax, caspase3, BCL-2), and synaptic (SYP, PSD-95, and GAP-43) proteins were examined using the western blot method. In addition, the histological evaluation was performed to assess tissue damage. The administration of Varenicline at the dose of 3 mg/kg reduced the IL-1ß, TNF-α, Bax, and caspase3 levels. Moreover, it increased BCL-2, SYP, PSD-95, and GAP-43 levels at the same dose and ameliorated memory impairment and anxiety-like behaviors in mPFC ischemic mice. Varenicline improved cognitive impairment by blocking inflammation and apoptosis, improving synaptic factors, and diminishing tissue damage in the mPFC ischemic mice.


Assuntos
Apoptose/efeitos dos fármacos , Isquemia Encefálica/complicações , Disfunção Cognitiva/tratamento farmacológico , Doenças Neuroinflamatórias/tratamento farmacológico , Agonistas Nicotínicos/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Vareniclina/farmacologia , Animais , Ansiedade/tratamento farmacológico , Ansiedade/etiologia , Comportamento Animal/efeitos dos fármacos , Isquemia Encefálica/imunologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/fisiopatologia , Disfunção Cognitiva/imunologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/fisiopatologia , Modelos Animais de Doenças , Camundongos , Doenças Neuroinflamatórias/imunologia , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/fisiopatologia , Agonistas Nicotínicos/administração & dosagem , Córtex Pré-Frontal/imunologia , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/fisiopatologia , Sinapses/metabolismo , Vareniclina/administração & dosagem
13.
Cells ; 11(2)2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-35053360

RESUMO

Alzheimer's disease (AD) is characterized by deficits in learning and memory. A pathological feature of AD is the alterations in the number and size of synapses, axon length, dendritic complexity, and dendritic spine numbers in the hippocampus and prefrontal cortex. Treadmill exercise can enhance synaptic plasticity in mouse or rat models of stroke, ischemia, and dementia. The aim of this study was to examine the effects of treadmill exercise on learning and memory, and structural synaptic plasticity in 3×Tg-AD mice, a mouse model of AD. Here, we show that 12 weeks treadmill exercise beginning in three-month-old mice improves spatial working memory in six-month-old 3×Tg-AD mice, while non-exercise six-month-old 3×Tg-AD mice exhibited impaired spatial working memory. To investigate potential mechanisms for the treadmill exercise-induced improvement of spatial learning and memory, we examined structural synaptic plasticity in the hippocampus and prefrontal cortex of six-month-old 3×Tg-AD mice that had undergone 12 weeks of treadmill exercise. We found that treadmill exercise led to increases in synapse numbers, synaptic structural parameters, the expression of synaptophysin (Syn, a presynaptic marker), the axon length, dendritic complexity, and the number of dendritic spines in 3×Tg-AD mice and restored these parameters to similar levels of non-Tg control mice without treadmill exercise. In addition, treadmill exercise also improved these parameters in non-Tg control mice. Strengthening structural synaptic plasticity may represent a potential mechanism by which treadmill exercise prevents decline in spatial learning and memory and synapse loss in 3×Tg-AD mice.


Assuntos
Hipocampo/fisiopatologia , Transtornos da Memória/prevenção & controle , Transtornos da Memória/fisiopatologia , Plasticidade Neuronal/fisiologia , Condicionamento Físico Animal , Córtex Pré-Frontal/fisiopatologia , Aprendizagem Espacial , Animais , Axônios/metabolismo , Espinhas Dendríticas/metabolismo , Proteína 4 Homóloga a Disks-Large/metabolismo , Hipocampo/metabolismo , Masculino , Camundongos Transgênicos , Córtex Pré-Frontal/metabolismo , Sinapses/patologia , Sinaptofisina/metabolismo
14.
Artigo em Inglês | MEDLINE | ID: mdl-34922998

RESUMO

Interactions among cortical areas of tinnitus brain remained unclear. Weaker alpha and stronger delta activities in tinnitus have been noted over auditory cortices. However, the interplay between a single substrate with whole brain within alpha/delta band remained unknown. Thirty-one patients with chronic tinnitus were recruited. Thirty-four healthy volunteers served as controls. Magnetoencephalographic measurements of spontaneous activities were performed. The strength of alpha/delta activities was analyzed. By dividing cortices into 38 regions of interest (ROIs), measurements of connectivity were performed using amplitude envelope correlation (AEC). Global connectivity was calculated by adding and averaging connectivity of single ROI with every other region. There were no significant differences in mean power of alpha and delta band between groups, despite the trend of stronger alpha and weaker delta band in controls. The global connectivity of alpha wave was significantly stronger in tinnitus for left frontal pole, and of delta wave for bilateral pars orbitalis, bilateral superior temporal, bilateral middle temporal, right pars triangularis, right transverse temporal, right inferior temporal, and right supra-marginal. The global connectivity of alpha/delta waves was enhanced for tinnitus in designated ROIs of frontal/temporal/parietal lobes. The underlying mechanism(s) might be associated with augmentation/modulation of tinnitus perception. Our results corroborated the evolving consensus about neural correlates inside frontal/temporal/parietal lobes as essential elements of hubs for central processing of tinnitus. Further study to explore the resolution of effective connectivity between those ROIs and respective substrates by using AEC will be necessary for the evaluation of pathogenetic scenario for tinnitus.


Assuntos
Ritmo alfa , Encéfalo/fisiopatologia , Ritmo Delta , Magnetoencefalografia , Vias Neurais , Zumbido/fisiopatologia , Córtex Auditivo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/fisiopatologia , Lobo Temporal/fisiopatologia
15.
Epileptic Disord ; 24(1): 211-218, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34753710

RESUMO

Longstanding epilepsy can lead to modulation of cortical networks over time and unexpected seizure onset zones. Frontal lobe seizures, in particular, can have diverse semiologies and evolution patterns. We present a male patient with drug-resistant epilepsy secondary to severe traumatic brain injury who underwent bilateral stereo electroencephalography (SEEG) for surgical planning. SEEG localized an ictal circular head roll to the right anterior prefrontal region. This was followed by spread to the left orbitofrontal region and later the left amygdala and hippocampus, at which point a different semiology with behavioral arrest, lip smacking and oral automatisms began. This case, in which an ictal circular head roll was localized to the anterior prefrontal region, demonstrates the complexity of broad seizure networks that develop over time, leading to remote seizure spread.


Assuntos
Epilepsia Resistente a Medicamentos , Córtex Pré-Frontal , Convulsões , Epilepsia Resistente a Medicamentos/fisiopatologia , Eletroencefalografia , Humanos , Masculino , Córtex Pré-Frontal/fisiopatologia , Convulsões/fisiopatologia
16.
J Neurosci ; 42(1): 109-120, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34759030

RESUMO

Decisions about what to eat recruit the orbitofrontal cortex (OFC) and involve the evaluation of food-related attributes such as taste and health. These attributes are used differently by healthy individuals and patients with disordered eating behavior, but it is unclear whether these attributes are decodable from activity in the OFC in both groups and whether neural representations of these attributes are differentially related to decisions about food. We used fMRI combined with behavioral tasks to investigate the representation of taste and health attributes in the human OFC and the role of these representations in food choices in healthy women and women with anorexia nervosa (AN). We found that subjective ratings of tastiness and healthiness could be decoded from patterns of activity in the OFC in both groups. However, health-related patterns of activity in the OFC were more related to the magnitude of choice preferences among patients with AN than healthy individuals. These findings suggest that maladaptive decision-making in AN is associated with more consideration of health information represented by the OFC during deliberation about what to eat.SIGNIFICANCE STATEMENT An open question about the OFC is whether it supports the evaluation of food-related attributes during deliberation about what to eat. We found that healthiness and tastiness information was decodable from patterns of neural activity in the OFC in both patients with AN and healthy controls. Critically, neural representations of health were more strongly related to choices in patients with AN, suggesting that maladaptive overconsideration of healthiness during deliberation about what to eat is related to activity in the OFC. More broadly, these results show that activity in the human OFC is associated with the evaluation of relevant attributes during value-based decision-making. These findings may also guide future research into the development of treatments for AN.


Assuntos
Anorexia Nervosa/fisiopatologia , Comportamento de Escolha/fisiologia , Preferências Alimentares/psicologia , Córtex Pré-Frontal/fisiopatologia , Adolescente , Adulto , Feminino , Alimentos , Humanos , Imageamento por Ressonância Magnética , Adulto Jovem
17.
Brain Res Bull ; 178: 49-56, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34728230

RESUMO

Internet gaming disorder (IGD) has become an increasing mental health issue worldwide. Previous studies indicated that IGD was related to maladaptive risk-taking behavior. However, the relationship among risk-taking behavior, reflection level, and resting-state functional connectivity (rsFC) between brain regions in IGD individuals remains unclear. The current study combined resting-state fMRI and the Devil task to investigate this issue. The behavioral results suggested that IGD participants exhibited increased risk-taking behavior in the Devil task than healthy controls. Moreover, IGD participants' risk-taking behavior was positively correlated with their reflection level. As for fMRI results, IGD participants showed stronger rsFC between orbitofrontal cortex (OFC) and inferior frontal gyrus (IFG) than healthy controls. Additionally, the mediation analyses revealed that, among IGD participants, the rsFC between OFC and IFG fully mediated the relationship between reflection level and risk-taking behavior. Together, the current study highlighted that the altered rsFC between OFC and IFG in IGD individuals modified the relationship between their reflection level and risk-taking behavior, which might contribute to the understanding of neural mechanisms underlying risk-taking behavior in IGD individuals.


Assuntos
Conectoma , Transtorno de Adição à Internet/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Assunção de Riscos , Adulto , Humanos , Transtorno de Adição à Internet/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
18.
J Alzheimers Dis ; 85(1): 309-321, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34806601

RESUMO

BACKGROUND: Alzheimer's disease (AD) is characterized by a progressive decline in cognitive functioning for which there is a stark lack of effective treatments. Investigating the neurophysiological markers of symptom severity in AD may aid in the identification of alternative treatment targets. OBJECTIVE: In the current study we used a multimodal approach to investigate the association between functional connectivity (specifically between scalp electrodes placed over frontal and parietal regions) and symptom severity in AD, and to explore the relationship between connectivity and cortical excitability. METHODS: 40 people with AD (25 mild severity, 15 moderate severity) underwent neurobiological assessment (resting state electroencephalography (EEG) and prefrontal transcranial magnetic stimulation (TMS) with EEG) and cognitive assessment. Neurobiological outcomes were resting state functional connectivity and TMS-evoked potentials. Cognitive outcomes were scores on the Alzheimer's Disease Assessment Scale-Cognitive Subscale, Mini-Mental Status Examination, and a measure of episodic verbal learning. RESULTS: Greater contralateral functional theta connectivity between frontal scalp electrodes and parietal scalp electrodes was associated with poorer cognitive performance. In addition, significant correlations were seen between the contralateral theta connectivity and the N100 and P60 TMS-evoked potentials measured from electrodes over the left dorsolateral prefrontal cortex. CONCLUSION: Together these findings provide initial support for the use of multimodal neurophysiological approaches to investigate potential therapeutic targets in AD. Suggestions for future research are discussed.


Assuntos
Doença de Alzheimer/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Eletroencefalografia/métodos , Córtex Pré-Frontal/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Transtornos Cognitivos/diagnóstico , Potenciais Evocados , Feminino , Humanos , Masculino , Análise de Regressão , Estimulação Magnética Transcraniana
19.
Int Rev Neurobiol ; 161: 121-145, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34801167

RESUMO

Cannabis is the most used drug during adolescence, which is a period of enhanced cortical plasticity and synaptic remodeling that supports behavioral, cognitive, and emotional maturity. In this chapter, we review preclinical studies indicating that adolescent exposure to cannabinoids has lasting effects on the morphology and synaptic organization of the prefrontal cortex and associated circuitry, which may lead to cognitive dysfunction later in life. Additionally, we reviewed sex differences in the effects of adolescent cannabinoid exposure with a focus on brain systems that support cognitive functioning. The body of evidence indicates enduring sex-specific effects in behavior and organization of corticolimbic circuitry, which appears to be influenced by species, strain, drug, route of administration, and window/pattern of drug exposure. Caution should be exercised when extrapolating these results to humans. Adopting models that more closely resemble human cannabis use will provide more translationally relevant data concerning the long-term effects of cannabis use on the adolescent brain.


Assuntos
Canabinoides , Córtex Pré-Frontal , Adolescente , Animais , Canabinoides/toxicidade , Feminino , Humanos , Masculino , Modelos Animais , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiopatologia , Caracteres Sexuais
20.
Behav Brain Res ; 418: 113674, 2022 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-34798167

RESUMO

There is evidence indicating that people are more likely to take risks when they are sleep-deprived than during resting wakefulness (RW). The ventromedial prefrontal cortex (vmPFC) could have a crucial psychophysiological role in this phenomenon. However, the intrinsic patterns of functional organization of the human vmPFC and their relationship with risk-taking during sleep deprivation (SD) are unclear. This study investigated the relationship between functional connectivity in the vmPFC and cerebral cortex and the risk-taking tendency after SD. The study participants were 21 healthy college students who underwent functional magnetic resonance imaging twice in the resting state, once during RW and once after 36 h of SD. The vmPFC was analyzed bilaterally for functional connectivity between the regions of interest. Correlation analysis was performed to evaluate changes in functional connectivity between the vmPFC and the cerebral cortex and risk-taking before and after SD. A single night of SD produced a definite deficit in functional connectivity between the vmPFC and thalamus bilaterally and an increase in functional connectivity between the vmPFC and dorsolateral prefrontal cortex (dlPFC) and the parietal lobe. We also found that the likelihood of risk-taking was positively correlated with increased functional connectivity between the vmPFC and dlPFC and negatively correlated with decreased functional connectivity between the vmPFC and thalamus bilaterally. These results demonstrate that lack of sleep substantially impairs functional connectivity between the vmPFC and the cerebral cortex, which in turn predicts the risk-taking behavior found after SD.


Assuntos
Córtex Cerebral/fisiopatologia , Vias Neurais/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Privação do Sono/fisiopatologia , Adulto , Humanos , Imageamento por Ressonância Magnética , Masculino , Assunção de Riscos , Adulto Jovem
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